Production of trisazo dyes



Patented Aug. 18, 1931 UNITED STATES PATENT 'oFFicE] CHARLES S. DEWEY/OF HAMBURG, NEW YORK, ASSIGNOR TO -NATIONAL ANILINE & CHEMICAL COMPANY, INC., OF N YORK, N. Y., A CORPORATION OF NEW YORK.

PRODUCTION OF TRISAZO DYES No Drawing.

This invention relates to the production of new and valuable trisazo dyes for dyeing cotton and other fibres. Materials dyed with the new dyestuifs also form a part of the present invention. V

The new trisazo dyes of the present invention canbe obtained by coupling a diazotized 2-amino naphthalene disulfonic acid (first component) having the following probable formula SIO3H NHz wherein one Y represents hydrogen and the other Y represents a sulfo group, with an alpha-naphthylamine (second component) having the following probable formula wherein X denotes ahydrogen atom or an alkoxy group, diazotizing the resulting amino azo'compound and coupling it with a Cleves acid (1)-amino naphthalene-7 (or 6)-sulfonic (acid) (third component), diazotizing the resulting alnino-disazo dye and coupling it with 1-amino-8-hydroxy-naphthalene-4:-sulfonic acid (fourth component) to form an amino trisazo dye.

The new trisazo dyes are salts of an acid represented by the following probable formula: r

' sogH x in whichX represents a hydrogen atom or an alkoxy group, e. g., OCH OC H OC H 00 1-1 etc.', one Y represents a hydrogen atom andthe other Y represents a sulfo group, and one Z represents a hydrogen .Application filed June 5, 1929. Serial No. 368,741.

atom and the other Z represents a sulfo group. In the dry state and in the form of their sodium salts, they are dark. powders soluble in water, soluble in concentrated sulfuric acid giving blue solutions, andfrom a neutral oralkaline bath dye cotton grayish blue to bluish gray shades which are fast to light and washing and are capable of being discharged to a white by the action of sodium hydrosulfite.

The following example will further illustrate the invention, but it will be understood that the invention is not limited thereto. The parts are by weight.

E azamplef19.5 parts of Q-amino naphthalene-4.8-disulfonic acid are dissolved in 500 parts water and 28.5 parts of B. sulfuric acid and are diazotized at 08 C. in the usual manner using 1.3 parts sodium nitrite. An excess of sodium nitrite is to be avoided. To the diazo solution thus obtained there are added, with stirring, 8.6 parts of alpha-naphthylamine previously dissolved in 350 parts water and 9.3 parts of hydrochloric acid of 20 B., the temperature of the reaction mixture being kept below 10 C. by the addition of ice. When the coupling is complete, which ordinarily requires about 5 to-6 hours, the resulting solution of the mon- OH s,

sulfonic acid (1.7 Cleves acid) are added to the suspension. After stirring the mixture for several hours, 12 parts of sodium acetate are added, and the coupling completed by further stirring for some time. When the coupling is complete, the mixture is diluted to a volume of about 600 parts, and sufiicient caustic soda added (about 4.5 parts) to dissolve the precipitated amino-disazo compound. lhe solution is cooled to 0 C. and diazotized by the addition of 35 parts of hydrochloric acid, 20 B. and 4.5 parts sodium nitrite. A small excess of sodium nitrite does no harm. When the diazotization of the amino disazo dye is complete, the resulting solution of the diazo-disazo compound is added to 13.2 parts of 1.8-am1no naphtholl-sulfonic acid (S-acid) previously dissolved in 210 parts water, 8.8 parts of 50 per cent caustic liquor and 30 parts of soda ash, and cooled to 0 C. A slight excess of S-acid should be present throughout the coupling. When the coupling is complete, the trisazo dye is salted out, filtered, pressed, and

1 dried. Thenew'trisazo dye thus obtained is a sodium salt of an acid having the following probable formula:

503E and in the dry state in the form of its sodium salt is a dark powder soluble in water, soluble in concentrated sulfuric acid giving a dark greenish blue color. It dyes cotton from a neutral'or alkaline bath bluish gray to grayish blue shades which are of excellent fastness toward light and washing and are capable of being discharged to white by sodium hydro-sulfite. It dyes rayon shades similar to those obtained on cotton. It leaves both silk and acetyl-silk practically unstained.

Other valuable trisazo'. dyes may be' pronaphthylamine in place of l-naphthylamine as second component, and/or 1.6-Cleves'acid, or a mixture of 1.6 and 1.7 Cleves acid in place of 1.7-Cleves acid as third component.

I 6131...; 1. In the production of a trisazo dye, the

able formula:

process which comprises coupling a diazotized 2-amino naphthalene disulfonic acid having the following probable formula:

SOKH

wherein one Y represents hydrogen and-the other Y represents a sulfo group, with an alpha-naphthylamine having the following probable formula:

wherein X denotes a hydrogen atom or an alkoxy group, ClIZLZOtlZlIlg the resulting amino-azo intermediate andcoupling the-re,-;.

sulting diazo-azo compound with a Gleves.

acid to form an amino-disazo compound,-di.-.

soaH

in which X denotes a hydrogen atom or an alkoxy group, one Y represents hydrogen and the other Y represents a sulfo group,and oneZ represents a hydrogen atom'andthe other Z represents a sulfo group. I "fl.

4. As a new product, the amino trisazo dye having in the free state the following prob- I sonar in which X denotes a hydrogen atom or an alkoxy group, and one Y represents a hydroe gen atom and the other Y represents a sulfonic acid group.

5. As a new product, the amino trisazo dye having in the free state the following probable formula:

-N=NQN=N SOiH 0H NH:

in which X denotes a hydrogen atom or an alkoxy group.

6. As a new product, the amino trisazo dye having in the free state the following probable formula:

7. Material dyed with a dyestufi' of claim 3.

8. Material dyed with a dyestufi' of claim 4.

9. Material dyed with a dyestuff of claim 5.

10. Material dyed with the dyestuff (if claim 6.

11. As a new product, the amino trisazo compound having in the free state the following probable formula SOaH OH NH:

mas/mtagwgmm 12. Material dyed with the dyestuif of claim 11.

13. As a new product, the amino trisazo compound having in the free state the following probable formula SOQH OH NH:

14. Material dyed with the dyestufi of claim 13. y

In testimony whereof I aflix my signature.

CHARLES S. DEWEY. 

